Uses of alternative antibiotics to control bacterium growth in mango explants.
Andrade S. R. M. de, Faleiro F. G., Teixeira J. B., Pinto A. C. de Q., Radel G., Cordeiro M. C. R., Ramo V. H. V.
Author Affiliation: A. C. de Queiroz Pinto, G. Radel, M.C. Rocha Cordeiro and V.H. Vargas Ramo, Embrapa Cerrados, Km 18 Br 020, PO Box 08223, 73301-970, Planaltina, DF, Brazil.
: 541-546
Abstract : Bacterias, if they are not eliminated from the explant, compete for nutrients from the culture medium and also eliminate toxins in the medium modifying the normal development of the explant. The decontamination consists of microorganism elimination, preserving the explant to be regenerated. Studies were conducted to develop a protocol to control an endogenous bacterium of mango internodal segments for the introduction in plant tissue culture medium. The explants were submitted to treatments with ethanol, sodium hypoclorite and benomyl for surface decontamination. The results showed that the bacterium was gram positive and resistant to the antibiotics rifampycin (300 mg/litre), kanamycin (150 mg/litre), ampicylin (150 mg/litre), tetracycline (150 mg/litre), chloramphenicol (150 mg/litre), carbenicyllin (150 mg/litre) and streptomycin (300 mg/litre). However, the results demonstrated that the combination of sulphametaxazole + trimetroprim (80 mg + 16 mg/litre) or sulfamethoxazole (80 mg/litre) alone showed satisfactory result on the control of this endogenous bacterium, while trimethoprim (16 mg/litre) did not work alone. Preliminary results demonstrated that the inclusion of copper sulfate (25 and 50 mg/litre) into the nutrient medium controlled the endogenous fungi, but did not control the bacterium growth. Medium containing 1.0% propolis extract also controlled the bacterium development, but the explant growth was also affected.